Advanced Machining Method Research Articles

A review on progress trends of machining of Carbon Fiber Reinforced Plastics

In contemporary manufacturing industries, composite materials such as carbon fiber reinforced plastics (CFRPs) have become indispensable, finding extensive applications in aerospace, automotive, shipbuilding, high-tech sports equipment, and more. The exceptional chemical, physical, and mechanical properties of CFRPs, including high corrosion resistance, superior strength-to-weight ratio, high fatigue strength, and oxidation resistance, make them highly sought after. However, these very advantages pose significant challenges during machining due to the abrasive nature of composites, anisotropic mechanical properties, and poor thermal conductivity, which collectively exacerbate tool wear. This review paper addresses the critical need for innovative solutions to improve the machinability of CFRPs, a subject of paramount importance for advancing manufacturing efficiency and product quality. It comprehensively examines the latest research progress, current practices, and emerging trends in machining techniques such as turning, drilling (including reaming and countersinking), milling and grinding. The review delves into the influence of various cutting conditions, environments, and tool geometries. It also examines tool textures, materials, and coatings. Additionally, advanced machining methods, including vibration, thermal, and hybrid-assisted machining, are discussed. These factors impact key performance metrics such as cutting forces and torques, tool wear and life, chip morphology, surface roughness, and the quality of machined surfaces, including defect analysis. By synthesizing a vast array of literature for the first time, this paper highlights the most effective strategies to enhance machinability while extending tool life and improving surface finish. Notably, it underscores the innovative use of dry and flood lubrication, minimum quantity lubrication, cryogenic lubrication, and high-pressure cooling. Additionally, it emphasizes optimizing cutting tool geometry, employing diamond tools, and coating tools with TiN and TiAlN, alongside the application of heat treatment and hybrid machining methods, particularly those incorporating vibration machining techniques. This review not only identifies the current challenges but also proposes cutting-edge solutions, making it an essential resource for researchers and practitioners aiming to push the boundaries of CFRP machining technology.

Application of Taguchi Method, ANOVA Analysis, and TOPSIS Technique in Optimization of Process Parameters for Surface Roughness and Material Removal Rate in Electrochemical Machining of Al-SiC MMCs

Objectives: To evaluate the significance of advanced machining techniques, such as EDM, ECM, and USM, in increasing productivity and overcoming challenges associated with outdated Al-SiC MMC machining. To assess the surface roughness, tool wear, and machining cost implications of employing advanced machining methods for Al-SiC MMCs. Methods The parameters studied were voltage (V), feed rate (F), and electrolyte concentration (C) in electrochemical machining (ECM) of Al/15%SiC composites. To optimise process parameters, the Taguchi method for Design of Experiments (DOE) with an L27 orthogonal array was used. Signal responsiveness is optimised using the Taguchi approach. The Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS) is used to find optimal machining settings. Findings: The outcome of this research is that the parameters affecting surface roughness and material removal rate are voltage, electrolyte concentration and feed rate. The minimum Surface Roughness achieved by selecting the best combination level is A2, B3, C3 (smaller is better) i.e., voltage 20 V, feed rate (f) 0.4 mm/min., electrolyte concentration (c) 30 g/lit. The maximum Material Removal Rate achieved by selecting the best combination level is A3, B3, C3 (larger-is-better) i.e., voltage 25V, feed rate (f) 0.4 mm/min., electrolyte concentration (c) 30 g/lit. Novelty : In this work, TOPSIS technique paired with Taguchi method is used which is rarely studied by other researchers. TOPSIS technique provides the best optimal solution as compared to other techniques. Keywords: Al-SiC MMCs, ECM, MRR, Ra, Taguchi method, TOPSIS

Optimization of machining parameters & studies on characteristics of Monel k400 alloy using abrasive water jet Machining using ANFIS

The Monel k400 alloy is a nickel-copper based alloy with an excellent corrosion resistance that exhibits better weldability and high strength. Also, it exhibits excellent resistance to either rapid flowing brackish water or seawater. Monel k400 alloy (UNS N04400) is widely used in oil, chemical and marine industries. Therefore, machinability of material plays a vital role in adopting material. As a result, in the current work, Monel k400 is used and manufactured utilizing an advanced machining method called an AWJM to examine the impact of process parameters on the machinability of alloy. The purpose of this study was to investigate the effects of abrasive mass flow rate, nozzle traverse speed, and stand-off distance on surface roughness. Adaptive Neuro-Fuzzy Inference System (ANFIS) model is used in order to predict surface roughness upon varying Abrasive Water Jet Machining process parameters for a lesser prediction error. In AWJM process Mean Absolute Percentage Error (MAPE) in between experimental, predicted surface roughness is found to be 3.46% which reflects efficacy of ANFIS model in predicting of surface roughness was evaluated to an extent of credibility. Also, the coefficient of determination R2 is evaluated and found to be 0.943, which indicates a good fit for prediction using the model against measured surface roughness values.

Study on high-speed vibration cutting of titanium alloy considering cutting edge radii

Ultrasonic vibration cutting (UVC) is an advanced machining method used to improve machining performance and surface quality in the manufacturing industry. However, the separation characteristic disappears when the cutting speed exceeds the maximum vibration speed, which limits its wide application in high-speed machining. Therefore, this study used the finite element method (FEM) to study the high-speed vibration cutting (HVC) processing performance of titanium alloys. High-speed vibration cutting is a precision machining method with a smaller cutting depth and feed rate, so it is necessary to consider the influence of the cutting edge radii on the cutting process. The cutting edge radii on high-speed vibration cutting and the impact of the traditional cutting process are discussed. The results show that the change in the minimum uncut chip thickness caused by changing the cutting edge radii during precision cutting has a significant influence on the experimental results. In addition, a simulation model was established, and comprehensive numerical analysis and comparison of high-speed vibration cutting, ultrasonic vibration cutting, and conventional cutting (CC) were performed to tool wear, cutting temperature, cutting force, and stress distribution. The simulation results indicate that the tool wear depth of traditional cutting during high-speed cutting is up to three times that of high-speed vibration cutting. High-speed vibration cutting weakens the influence of the cutting edge radii, but this new vibration cutting method did not significantly reduce the cutting temperature under dry cutting conditions.

Grey relational analysis based particle swarm optimisation (PSO) of quality characteristics in laser cutting of titanium alloy sheet

ABSTRACT Machining of advanced engineering material like titanium alloy (grade 5) with precision and accuracy is an evolving requirement. The selection of an appropriate advanced machining method and range of cutting parameters is very essential to obtain high-quality cut and geometric accuracy. The traditional machining methods are incompetent to machine the titanium alloy sheet material due to its unfavourable mechanical and thermal properties and high chemical affinity at elevated temperature. The Nd:YAG laser cutting process delivers better cutting quality, precision and geometric accuracy. In this work, the regression method has been adopted for developing the empirical models of geometric quality characteristics such as kerf width, kerf deviation and kerf taper. These developed models have been optimised using grey relational analysis based particle swarm optimisation in order to ascertain the optimal range of cutting parameters pertaining to better cut with high precision and geometric accuracy. The optimisation results show individual improvement in top kerf width, top kerf deviation and kerf taper of 28.88%, 13.33% and 56.52%, respectively, and 17.42% against the initial settings for multiple performance index. Finally, the effects of input process parameters on output quality characteristics have also been investigated.

DEVELOPMENT OF ELECTRIC DISCHARGE MACHINING (EDM) USING SOLENOID ACTUATOR FOR EDUCATIONAL PURPOSE

The increasing number of materials with variation in properties, especially hard-to-cut, leads to the need for an advanced machining method to process such material. Electric Discharge Machining (EDM) is one of the advanced machining methods widely used for hard-to-cut alloys. The EDM process uses an electrode as the conductor of electrical current to erode the metal alloys and is supported by other components. Due to EDM's high cost and high energy consumption, developing a low-cost EDM and simpler EDM setup is necessary, especially for educational purposes in laboratory activity. However, the EDM design and setup required to produce the desired “spark” have always been a challenge for researchers and manufacturers. In this research, a small-scale EDM setup was built. A solenoid actuator is used to generate simple mechanical movement. The movement is used to control the gap between the workpiece and the electrode to produce a spark. The solenoid actuator is used because of its low cost and simple mechanism. The proposed EDM setup is successfully fabricated and works appropriately by generating sparks and a hole cavity during the process. There are six cavity holes produced in mild steel workpiece during the experiments with various parameters such as current (5A, 7A, and 10A) and frequency (10 Hz and 20 Hz). The varied parameter shows that the higher current and lower frequency removed more materials. In contrast, the higher frequency produced a better quality of the cavity hole. However, the lack of flushing quality on the material debris during the process results in the formation of excess metals around the edge of the hole.

An Effect of EDM on AL6061-5% SiC as stir cast MMC

Usage of advanced machining method in the formation of composites made of aluminum metal matrix (Al-MMC) has produced substantial ability because the manufacture of intricate die shapes in these tough material is of elevated precision and surface finish Impossible. EDM has proven to be one of the many unorthodox processing techniques that are successful in shaping These materials which are difficult to process. The main aim of this investigation work is to find the outcome of Pulse ON-time (Pon), Current (Cu)and flushing pressure (Fp) on tool wear rate (TWR), metal removal rate (MRR) taper (T), radial overcut (ROC), and surface roughness (SR) on machining Al6061 with 5% SiC reinforcement.[1,2] On this Investigation we are deputed Electronica PSR 35 and dielectric fluid was used as kerosene with the help of flushing machine to pump out the dielectric fluid. Copper is used as the electrode and it also used as a tool of diameter 3mm to pierce the work piece for the required length. Three machining parameter at each having three stages was used to perform the experiment on the orthogonal array of L27 taken into account. The experiments are conducted for three following trails in random order. The maximizing taken into account for optimization and ANOVA statistical tool is used and to find out the surface morphology SEM is taken on different parts of the work piece.[3]

Recent Advances and Perceptive Insights into Powder-Mixed Dielectric Fluid of EDM.

Electrical discharge machining (EDM) is an advanced machining method which removes metal by a series of recurring electrical discharges between an electrode and a conductive workpiece, submerged in a dielectric fluid. Even though EDM techniques are widely used to cut hard materials, low efficiency and high tool wear remain remarkable challenges in this process. Various studies, such as mixing different powders to dielectric fluids, are progressing to improve their efficiency. This paper reviews advances in the powder-mixed EDM process. Furthermore, studies about various powders used for the process and its comparison are carried out. This review looks at the objectives of achieving a more efficient metal removal rate, reduction in tool wear, and improved surface quality of the powder-mixed EDM process. Moreover, this paper helps researchers select suitable powders which are exhibiting better results and identifying different aspects of powder-mixed dielectric fluid of EDM.

Analysis of Surface Characteristics for Al–SiC Metal Matrix Composites Machined by Wire Electrical Discharge Machining (WEDM)

Objectives: The application of light weight products used for automobile needs to require the use of Al metal matrix composites (MMCs). The optimized combination of process variables has been found to accomplish for better machining. Methods/statistical analysis: There is different type of machining methods used for machining of MMC but it is not so easy to machine these materials with full efficiency and desired output responses because of difficult to machine these materials as compared to other unreinforced materials like alloys and smart materials. The main reason behind hardness of aluminum MMCs is heterogeneous structure which makes its surface layer with high fatigue strength, smooth, and tough. L9 orthogonal array has been used to perform the experiments. Findings: The effect of parameters has been calculated and analyzed for response analysis. The effect of various machining parameters like wire diameter, current, voltage, pulse on time, and pulse off time is observed and analyzed on surface properties of the Al–SiC MMCs. As a result of compressive residual stress on the surface that is a plus point for material to use it for tough work, but along with this it will cause high tool wear and surface imperfections while machining, so these are some reasons for the recommendation of non-conventional machining methods to machine aluminum matrix composites. So, several new techniques were added in some past few years of research which is explained in this research article. Application/improvements: Wire electrical discharge machining (WEDM) which is an advanced machining method which is used for manufacture difficult shapes conductive work piece materials. Experimental work will be done on the WEDM of Al–SiC MMC. Keywords: Aluminium Metal Matrix Composite Al–SiC, Surface Roughness, Wire Electrical Discharge Machining (WEDM), Surface Integrity, Taguchi’s Method, Response and Regression Analysis.

Optimisation of Process Parameters for Minimising the Surface Roughness During Wire-Electrical Discharge Machining (WEDM) of Silicon Particle Reinforced Al6061 Composite

In the recent era, the advanced machining methods are popularly used for machining of simple to complex profiles in engineering materials. In this work, the machinability of 8 % silicon particle reinforced Al6061 composite is investigated by WEDM. The effect of control parameters namely current (Ic ), pulse-off time (Toff), wire-speed (Ws ), pulse-on time (Ton) and voltage (Iv ) on surface roughness is investigated. Taguchi L16 orthogonal array is used in the experimental design and the results are analysed using statistical methods. Study showed that, the Tonis the highly significant parameter which contributed maximum (38.27%) to variation of surface roughness followed by voltage (31.02 %), wire speed (17.11 %), current (7.11%) and pulse-off time (5.39 %). The optimum settings which produced the minimum surface roughness (expected Ra- 3.302 µm) are current: level 3 (4A), Ton: level 1 (20 µs), Toff: 10 µs (level 1), Ws- level 4 (1400 rpm) and voltage - 80 V (level 1). The regression model is developed for predicting the surface roughness with � 2 value of87.30%. The model predicting accuracy of the model is verified for the experimental results.

E nhancement of Surface Quality of AISI D3 Steel after Electrical Discharge Machining (EDM) with Aluminium P owder M ixed in the Di electric

Electrical Discharge Machining is an advanced machining method with various advantages, as a result of which, its use is becoming more & more widespread. This process is one of the modern machining processes which is characterized by the absence of plastic deformation and chip formation. The advancement of this process may further be enhanced by utilizing powder particles within dielectric medium that is designated as Powder Mixed Electrical Discharge Machining (PMEDM) process. In the current study, to enhance the surface roughness (SR) of AISI-D3 tool steel using Copper and Brass as electrode and Aluminium (Al) as powder by utilising PMEDM process, an experimentation has been carried out. During experimentation, pulse on and off time, peak current and powder concentration are considered as input process parameters. From the experimental results, it is noted that with mixing of aluminium powder in dielectric medium, surface roughness has increased significantly. Moreover, it is seen that powder concentration of 1 g/l at 1 A peak current giving better surface quality of AISI-D3 steel. This indicates the enhancement of Electrical Discharge Machining (EDM) performance dispersing aluminium powder in dielectric fluid.

Modal Analysis of Ultrasonic Horn using Finite Element Method

Abstract Ultrasonic Machining (USM) is a preferred advanced machining method for hard and brittle material. This process can be conveniently combined with other machining processes to develop different hybrid machining processes. The machining capability of the USM process largely depends on the amplification of the amplitude of vibration produced by transducer. The ultrasonic horns vibrate in longitudinal direction and transfer the vibrational energy from transducer to workpiece. The design of ultrasonic horn is utmost important because incorrect design not only deteriorate the machining performance but also the cause damage to the vibration system and generator. In this study, modal analysis of two different horn profiles which are comparatively difficult to manufacture i.e. steeped and exponential have been performed using finite element based ANSYS software. Mode shape and natural frequencies of the above two profiles made of Titanium and Aluminium have been taken into consideration. From the result it is observed that for stepped profile Titanium horn produces higher natural frequency for all the six modes but in case of exponential profile Aluminium horn produce more frequency than Titanium alloy.

Multi Objective Optimization of Wire EDM Machining Parameters for AA7075-PAC Composite Using Grey - Fuzzy Technique

Wire cut discharge Machining is an advanced machining method controlled by a variety of interrelated complex parameters like discharge current, pulse on time, pulse off time and servo speed rate. Any slight variations in one will have an effect on the machining quality measures like surface roughness and material removal rate. In the present work Aluminium 7075 is used as matrix and activated charcoal with different percentage as reinforcement to fabricate metal matrix composites. The specimens are tested for Density, Hardness, Impact Strength and Ultimate tensile Strength. Best chosen samples are used to perform machining process in wire cut electrical discharge machine. 27 trials of experiments based on Response surface methodology are done and the observations are made. The quality of the machined samples is evaluated by the measurement of material removal rate and surface roughness. Results are utilized to develop the grey-fuzzy model. From this technique, the optimum combinations of process parameters are obtained and corresponding values of maximum material removal rate and minimum surface roughness are found out. From ANOVA analysis it is found that servo speed is the significant factor in determining the machining quality. Confirmatory experiments are performed to determine the effectiveness of the approach.

Influence of Machining Parameters on Machine Tool Loads at Rotary Ultrasonic Machining of Cubic Boron Nitride

Poly-crystalline cubic boron nitride (PCBN) is one of the hardest known material. Therefore only advanced methods are able to treat such material. Advanced machining methods, proper for machining of hard and brittle materials (such as glass and ceramics) include rotary ultrasonic machining (RUM). However, high hardness of workpiece cause higher loads and it could negatively affect achievable accuracy and surface topography. Machine loads are affected by both: machined material and machining parameters. This contribution investigates influence of machining parameters, such as spindle speed, feed rate and depth of cut, on loads of machine tool during machining of PCBN by rotary ultrasonic machining.

Influence of Machining Parameters on Surface Topography of Cubic Boron Nitride at Rotary Ultrasonic Machining

Poly-crystalline cubic boron nitride (PCBN) is one of the hardest known material. Therefore only advanced methods are able to treat such material. Advanced machining methods, proper for machining of hard and brittle materials (such as glass and ceramics) include rotary ultrasonic machining (RUM). This method should achieve high precision and low surface roughness (at least during machining of materials such as ceramics). Achievable roughness is affected by machined material and machining parameters. This contribution investigates influence of machining parameters, such as cutting speed and feed rate, on resultant surface roughness during machining of PCBN by rotary ultrasonic machining.

Analytical, numerical and experimental study of cutting force during thermally enhanced ultrasonic assisted milling of hardened AISI 4140

Two advanced machining methods as thermally enhanced machining and ultrasonic assisted machining has been considered in many studies, recently. In this paper, a new hybrid milling process is presented by gathering the characteristics of these two methods. A special experimental setup is applied and numerical and analytical models are developed to predict cutting force during the hybrid process. 3D thermal finite element analysis is applied to determine the axial depth of cut and engagement (the radial depth of cut) by measuring the dimensions of softened material. Full factorial experimental design is applied to investigate the effect of hybrid machining parameters on the mean cutting force. 2D finite element model is developed to predict the mean cutting force of the hybrid milling process. The analytical model is developed based on chip thickness as well as consideration of thermal softening of the material caused by the concentrated heat source. Major events in numerical and analytical models are external concentrated heat source and ultrasonic vibrations that are implemented successfully. According to the results, the application of thermally enhanced ultrasonic assisted milling on hardened AISI 4140 with the amplitude of 10µm and temperature of 900°C could reduce cutting force about 27% in comparison to conventional milling with feed of 0.063mm/tooth. Experimental results presented a good agreement with numerical and analytical methods which can show the ability of developed methods to predict mean cutting force.

Experimental Study of Surface Roughness and Tool Flank Wear during Hybrid Milling

Two advanced machining methods such as thermally enhanced machining and ultrasonic-assisted machining are recently considered in many studies. In this article, a new hybrid milling process is presented by gathering the characteristics of these two methods. In order to determine the axial depth of cut and engagement in the process, three-dimensional thermal finite-element analysis is applied to determine the dimensions of softened materials. Finite-element modal analysis is used to determine the dimensions and clamping state of the workpiece while cutting area has the highest vibration amplitude. Full factorial experimental design is applied to investigate the effect of hybrid machining parameters on the surface roughness and tool wear. Tool flank wear was investigated under the condition of constant cutting speed during different period of times. Hybrid milling process with an amplitude of 6 µm and a temperature of 900°C creates a surface with 42% lower roughness in comparison to conventional milling in feed 0.08 mm/tooth. In a study of tool flank wear, the results show that application of TEUAM decreases flank wear at least 16% in comparison to all other processes.

Surface Roughness of Poly-crystalline Cubic Boron Nitride after Rotary Ultrasonic Machining

Rotary ultrasonic machining (RUM) is suitable particularly for machining hard and brittle materials, such as glass and ceramics. This contribution investigates the machining of poly-crystalline cubic boron nitride (PCBN) by using this advanced machining method. In the experiment, a tool for friction stir welding (FSW) was manufactured. Such tool is 1 pprox.1 for welding the materials with enhanced mechanical properties. The research was focused on machined surface roughness, because roughness has a significant influence on the welding process, especially on sticking ability. If roughness of the tool is too high, the welded material will stick on the tool and the weld cannot be fabricated. According to the performed experiment, RUM seems to be a proper method to manufacture a FSW tool, owing to the low roughness achieved (Ra 0.24μm).

Rotary Ultrasonic Machining of Poly-Crystalline Cubic Boron Nitride

Abstract Poly-crystalline cubic boron nitride (PCBN) is one of the hardest material. Generally, so hard materials could not be machined by conventional machining methods. Therefore, for this purpose, advanced machining methods have been designed. Rotary ultrasonic machining (RUM) is included among them. RUM is based on abrasive removing mechanism of ultrasonic vibrating diamond particles, which are bonded on active part of rotating tool. It is suitable especially for machining hard and brittle materials (such as glass and ceramics). This contribution investigates this advanced machining method during machining of PCBN.